Timer



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Patented Sept. l5, 1925.

EDWIN savant), or VENTURA, cnLiroRNIA.

TIMER.

Application VfiledAIn/Iarch 3, 1924. Serial No. 696,409.

citizen of the United States, residing atA Ventura, in the county of`Ventura and 4State of California, have invented new and usefulimprovements in Timers, of which the following 'is a specification.

This invention relates to timers of the character employed in theignition circuits of internal combustion motors and ris an improvementon the timer patented to me September 18, 1928, No. 1,468,405. In saidformer patent contact was made with a ring mounted on an eccentric,turning of the eccentric causing the ring to contact in succession witha series of spring pressed ball contacts.

According to the present invention electric contact elements ride on theperiphery of an insulation ring that is flattened at a point in itsperiphery to permit the contact elements in succession, as theinsulation ring rotates, to contact with a metal ring of smallerdiameter than the insulation ring. The metal contact ring is preferablyloosely mounted so that the friction of the contact elements, when 'theyengage said ring contact, causes the metal ring to turn slightlyrelative to the insulation ring, thereby to cause constantly newsurfaces to be presented for engagement'by the contactelements, thuswearing the contact ring more evenly than would be possible if saidcontact and insulation rings were in fixed relation.

The accompanying drawings illustrate the invention Fig. 1 is a frontelevation Aof a timer embodying the invention, the case being mainly insection so as to disclose the mechanism therein.

Fig. 2 is a longitudinal midsection of the timer shown in Fig. 1.

Fig. 8 is a perspective view of the frustoconical cap for making easythe slipping ,of the roller contacts into place upon the rperiphery ofthe insulation andcontact rings.

A portion of the front wail of the housing of the cam shaftoperating-gears of the motor is shown at 4, and may be recessed asindicated at 5. The wall 4 supports a bearing .6 in .which rotates thecam shaft 7 f the motor, only a fragment of said cam shaft being shownin Fig. 2. Fitting in the recess 5 is the timer cover V8. The parts sofar described are well known in the art pertaining to timers, especiallyto that type of timer used on a well-known make of light automobiles.rlhe shaft 7 is provided with a shoulder 9 against which the inner endof the bearing 6 thrusts, said shoulder inwardly terminating a reducedportion 10 of the shaft 7 and said portion 10 being journaled in thebearing 6. n

Mounted on the forward end of the reduced shaft portion 10 is a collarcomprising an annular flange 11 and a reduced portion 12, said flangethrusting against the outer end of the bearing 6. The collar 11, 12 isdetachably fastened to the shaft 10, to rotate therewith, by a headedpin 18 which entends through a perforation 14 in the collarand engages ahole 15 extending transversely through the shaft 10.

Mounted on the reduced portion l2 of the collar, adjacent to the fiange11, is an insulation ring 16, which is flattened at one point on itsperiphery to form a low point indicated at 17. The insulation ring maybe secured to the collar by suitable means as, for example, rivets 18.

Rotatably mounted relative to the collar is an electric contact ring 19of metal. ln this particular instance the contact ring 19 is vnotmounted directly upon the reduced portion 12 of the collar but upon theren duced portion 20 of an outer collar which also comprises a flange 21to hold the ring 1'9 toward the insulation ring 16. The outer collar isalso held in place by the pin 18 which passes through a hole `22 in said,outer collar.

It will be noted that the insulation ring 16 is of larger Ydiameter thanthe` contact ring 19 excepting at the low point 17. At said ,low pointthe radins of the insulation ring is less than the radius of the contactring, but the actual difference is so slight that 'it is more or lessexaggerated in the drawings.

Adapted to ride on the peripheral face of the insualtion ring 16 is anelectric contact or contacts 28, preferably in the form of rollers.These rollers are each rotatably mounted on a U-shape arm 24 which ispivotally carried at 25 on a bracket 26 secured to the inner face of thecase 8 by a binding post 27 that extends to the outer face of the case 8and that is insulated from said case by an insulation bushing 28. rlhusan electric circuit is established through wires, not shown, attached tothe binding posts and through the contact rollers 23, arms 24, brackets26 and binding posts 27. ln this particular instance four contactrollers 23 are shown as this particular timer is designed for a fourcylinder motor. On each pivot 25 is a coil spring 29 having one endbearing against the associated arm @-1 and its other end againstthebracket 26, the arrangement being such as to press the arms 2d towardthe center of the case.

It will now be clear that, when the timer shaft 7 is rotated, it effectsrotation of the insulation ring 16 which, in turn, causes rota'lion ofthe rollers 23. As the low point 17 of the insulation ring comesadjacent to each of the rollers 23, the actuating spring 29 of saidroller urges the roller inwardly into contact with the peripheral faceof the ring 19 which, not being insulated from the shaft 7, completesthe circuit through one of the spark plugs, not shown, connected incircuit with the timer. Each time a roller 23 engages the ring 19 thefriction between itand said ring is sufficient to retard rotation of thering 19 suiiiciently tov cause relative rotation between said ring andthe insulation ring 16 so that, when the low point 17 again rotates intoposition adjacent to the same roller 23, said roller will contact with adifferent place in the periphery of the contact ring 19. Because of thering 19 being loose on the collar 20, Q1 more uniform wearing of thering 19 occurs than if said ring were in fixed relation to the shaft 7.j

It will be noted that the head of the pin 13 is covered by a cap 30which is held in place by a nut 31 threaded onto the outer end of theshaft 7. The rim of the cap 30 fits over the periphery of the flange 21and is preferably of frusto-conical shape so that, when the case 8 withits rollers 23 mounted therein, is pushed into place during theassembling of the timer, the tapered face of the cap 30 will function towedge al1 of the rollers 23 outwardly against the pressure of thesprings 29, thus spreading the rollers sufficiently to admit of theentrance therebetween of the rings 16, 19. rI`he cap 30 covers the headof the pin 13 and prevents said pin from falling out of place.

It will be clear from the foregoing that the insulation ring 16constitutes a cam and the rollers- 23 follower contacts, and that saidcam alternately functions to lift the follower contacts off of the ringcontact and permit said follower contacts to be returned by the springinto engagement with said ring contact.

I claim:

1. In a timer, the combination of an insulation cam, means to turn thecam, a moyably mounted metal follower contact projecting beyond one sideof the cam, means yieldingly holding the follower contact engaged withthe cam, and a metal contact mounted to one side of the cam in positionto be engaged by the follower contact when the low point of the camcomes adjacent to said follower contact.

2. In a timer, the combination of an insulation cam, means to turn thecam, a moyably mounted metal follower contact projecting` beyond oneside of the cam, means yieldingly holding the. follower contact engagedwith the cam, and a metal ring contact of smaller diameter than the cammounted to one side of the cam in'position to be engaged by the followercontact when the low point of the cam comes adjacent to said followerlcontact.

3. In a timer, the combination of an insulation cam, means to turn thecam, a movably mounted metal follower contact projecting beyond one sideof the cam, means yieldingly holding the follower contact engaged withthe cam, and a metal ring contact of smaller diameter than the camrotatably mounted relative to the cam and to one side thereof inposition to be engaged by the follower contact when the low point of thecam comes adjacent to said follower contact.

et. In a timer, the. combination of a collar, an insulation cam securedto the collar, means to rotate the collar, a movably mounted metalfollower contact, means yieldingly holding the follower contact engagedwith the cam, an outer collar mounted on the first collar adjacent tothe insulation ring, and a metal ring contact of smaller diameter thanthe cam mounted on the outer collar 'in position to be engaged by thefollower contact when the low point of the cam comes adjacent to saidfollower contact.

5. In a timer, the combination of a collar, an insulation cam secured tothe collar, means to rotate the collar, a movably mounted metal followercontact, means yieldingly holding the follower contact engaged with thecam, an outer collar mounted on the first colla-r and having a flange,and a metal ring contact of smaller diameter than the cam mounted on theouter collar between the flange and insulation cam, the follower contactengaging the ring` contact when the low point of the cam comes adjacentto said follower contact.

Signed at Los Angeles, California this 23d day of February 1924.

EDIVIN E. SAVARD.

